实参形参不兼容

Question

代码如下

include<stdio.h>

extern char GetString(char pString);
extern void ShowString(char* pString);

int main()
{

char* pMyString;


pMyString = GetString("Hello!");
ShowString(pMyString);


return 0;

}

extern char GetString(char pString)
{

return pString;

}

extern void ShowString(char* pString)
{

printf("%s\n", pString);

}

如何改正